The figure on the next page appeared in the paper ?EDTA-Extractable Copper, Zinc, and Manganese in Soils of the Canterbury Plains? (New Zealand Journal of Agricultural Research [1984]: 207?217). A large number of topsoil samples were analyzed for manganese (Mn), zinc (Zn), and copper (Cu), and the resulting data were summarized using histograms. The investigators transformed each data set using logarithms in an effort to obtain more nearly symmetric distributions of values. Do you think the transformations were successful? Explain.

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Untransformed data Log-transformed data 30 Cu Cu 20 10. 0.5 1.0 1.5 2.0 -0.6 0.0 30 Zn Zn 10 0.5 1.0 1.5 2.0 -0.6 0.0 30 Mn Mn 20 10 15 30 45 60 1.0 2.0 ug/g log10(ug/g) Number of samples Number of samples Number of samples 20 is